Electrical connector



Nov. 20, 1945. L. L. STOFFEL ETAL ELECTRICAL CONNECTOR Original Filed Dec. 12, 1941 16454. 720mm bl'fiam.

Patented Nov. 20, 1945 ELEGTRIGAL GONN-ECTOR' Lester L. Stoffel,. Lakewood, and Alfred. A; Stark,

Cleveland, Ohio, assignorsrtol The Ohio Carbon. Company; Cleveland, Ohio; a corporation. of

Original.applicationDecembenrZ; 1941,,SerialzNo";

422,752. Divided and this-application Septeme" ber..11, .1943',.Serial;No. 501,964:

5 Claims:

'ITiis inventionirelatesto an.-electrical connemtor, and" particularly to aneleotrical. connectoradapted to carry a resisting deviceandbe in serte'd between anlelectricconductor and a spark plugfor making the. connection between the con. ductor andlplug .and introducing a resistor adapt edto' suppress a sparkat the connection. to the. plug. Such devices are in .use for the purpose of. preventing interference with radio. reception on an automobile due to the leakageor other irregue lar actions" of the." ignition circuit. lihe present. application isadivision of 'our copending applica tion, Serial No. 4221752: fil'edYDecember. 12, 1941,. issued asiPatentNo. 2',35'3,'199"on July. 11, .1944;

Our invention is concerned with an. electrical. connector" for: carrying a. resisting, or other electical elementand effectively connecting; itto the spark plug. Severalembodiments ofltheinvention' are shown in the drawing hereof and are. hereinafter more fully described, while'the'essential novel characteristics are summarizedlinlthe. claims;

the drawing; Fig; 1 is a sectionalsideele- I vationof on'e side of our resistor in placebetweena spark'plugand'the conductor. therefbr.;. .Fi'g.. 2; is an" exploded" view of" the parts oftheresist'or shown in'Fi'g. I; Fig. 3Iis a'crosssectionthrough the'body'of. the resistor'as indicatedlb'y the. line. 3 -3 in Fig; 2; Fig, 4 is a side elvationpartlm broken away andpartly. in section of. a modified form.of"our"resistor; Fig. 5"is a vertical'cross.sec-- tion on the line 5'5' onFig. 4,.and Fig. GTisa-l longitudinal axial sectionxofthe resisting element,

In Fig. 1, .A.indicates. a sparkplug, having, a conductingstem with an annular? groove etherein. B indicates. the head" of; a conductor. which. terminates in a split sleeve having, inward. projections b" adapted to engage'in the groove a..ofi the'pliig when no resisting device is present. Our

resisting device in any of the.formsillustratedis. A

adapted to be mounted on the. spark pliigandf electrically and mechanically connect. with. the. conducting. groove a thereof'iand also witlithe. two. spring projections. bl. offthe supply; line.

Referrin first to the connecting device shown in Figs; 112-, and..3, .l llfindicates a cylindrical body of insulating' material-ihaving a central bore H leading from one end. This body carries a metallic sleeve [2 which is embedded in the end portion of the body and extends beyond it and around a reduced portion l3 of the body, and is provided with an annular groove Hi to receive the projections 1) of the conducting cable B.

Inserted in the bore II is a resisting element 20 which may be a round stick of carbon.

indicatesa: metallic. plug, which: may be of lead;. sea-ted: in l the: endnportioni of: the metallic; sleeve; I2;- which preferably flaresinLthis' region. This. plug is thus in electric contact with thei'metallic sleeve li -and alsorwith the resistingelementt2 lb springiiscompressed: between the; resisting ele-'- ment 'andian' abutment. (to be described) carried bythe body; 'Ihespringt26-engages one endiofr the-resisting element:20 and'forces the-other end against the plug 252 The resisting; element preferably carries-suitable:

conductingl-metal at each end. To make a good connection between themetallic end and the carbon; body. of: theresistor, we: first: spray" the end of the resistor with mclden copper to producewa layer" 2 l:- adhering: to: the" resisting element,-, and

theniwevapply ailayer: 0fsolder 22'to the outside of this=copper layer; as indicated inzFig. 6.

The. means. to. connect our device: to.-the spark plug, comprises anexternal coiled spring. 3ll-adapted to overlap: the stem of. the plug: and seat ininternal :springzZtr Thatzis to say, this Wood screw.

is turned'inafrom a position diametrically oppositesthe spring extensionv 3 l: and screws into such. extension, thus expanding it and lockingait to-the body "has shown in-Fign-l, and at the-samettim'e establishing a goodelectricconnection to.- the spring; 26 F which leads; to the metallic. end of the. resisting; e1ement 20;

It-=wil11beseen that when the parts-shown in.

Fig; 21816 assembledthey produce theconstruew tion of Fig; 11-. and provide a xsimple device readily. attachable-to the sp ark: plug; and to theconductor normally; connecting directlytto the plug; and .thus

introduce insthe: circuit a1 resisting; element. Theresistance of this resistin element exceeds the resistance between any other meeting parts of the connection from the conductor to the spark plug and thus operates to suppress any spark which might otherwise form at such junction and thereby reduces the interference with any radio equipment.

In the embodiment of Fig. 4, the metallic sleeve In Fig. 4, the body lflc is slightly differently formed. It carries the resisting element 20 backed up by the compression spring 26, but the inner end of the spring is engaged by a screw 50 which engages an axially threaded extension of the bore in the body. The clamping screwpasses through a loop 34 on the spring Sila so that the head of the screw not only clamps the spring to the body I00, but is in good electrical connection therewith. The inner end of the screw bears against the internal spring 26, which at its other end bears against the resisting element 20. The extreme end of the body lac is circularly recessed at l8 to receive the loop of the spring 30a, and the body also has a radial recess I9 to receive the extension of the loop leading to the open coil 3011 as is illustrated in Fig. 5.

In each of the embodiments shown, the resisting element is housed within an insulating body and is in good electrical connection to the open spring coil 39 which engages the sparkplug. This open spring provides a yielding mechanical support for the conductor and resistor so that they are not likely to jar loose in the travel of the car. In each embodiment, the external spring is in good electrical connection to the internal spring which bears against the metallic end. of the resisting element and operates to press said element so that its other end is maintained in good metallic connection with the plug connected to the terminal which the spring sleeve of the conductor engages.

It is to be understood that in each of the views, the parts are shown on a considerably larger scale than is normally employed in practice. The simple little device illustrated is readily mounted whenever desired by simply pulling the normal conductor free from its plug and attaching the resistor to the plug and the conductor to the resister. The conductor is thus maintained approximately in its normal'position and serves to conduct the sparking current to the plug without danger of extraneous sparks to interfere with radio operation.

While our improved connecting device has been illustrated as carrying a resistor for use in connection with a spark plug of a motor vehicle, it is obvious that it is readily adaptable for other uses, as for instance for carrying a fuse element.

We claim:

1. An electrical connector comprising an insulating body, a conductor carried thereby and projecting therefrom, a conducting element within the body, an electric connection at one end with the projecting conductor, an external spring having a portion adapted to engage one member to be connected and having an extension projecting into a lateral opening in the body, a screw inserted into the body from a position opposite the extension, said screw entering such extension and binding it to the body, and a compression spring within the body bearing at one end against the conducting .element and at the other end against the inward extension of the external spring.

2. An electrical connector, comprising an insulating body having a recess, a metallic sleeve pro- .jecting from the body and adapted to be externally engaged by a sleeve on the end of a conductor, an external coiled spring secured to the body and adapted to embrace the stem of a member to be connected to the conductor, an electrical conducting element within the recess, means for connecting it at its outer end to the sleeve carried by the body, a spring Within the body normally pressing against the inner end of the conducting element and having the other end thereof in electric connection with the external spring, and a screw' on the opposite side of the body from the external spring and axially entering the interior of spring turns within the body for clamping the external spring thereto, and maintaining it in electrical engagement with the internal spring.

3. An electrical connector comprising an insulating body having a bore, a metallic conducting sleeve carried by the bodyaandp rojecting beyond one end thereof andsuitable for engagement by an electric'conductor, an external metallic coiled spring secured to the body and having a portion thereof projecting at right angles to the body and adapted to embrace a device to be connected to the conductor, a, plug forming a conductor from the interior of the body to said conducting sleeve and conducting means including a compression spring within the body in, contact with the plug and the external spring, whereby an electric connection is established and maintained between the metallic sleeve and the external spring,

4. An electrical connector comprising body of insulating material having a pair of intersecting openings, a metallic coil spring having a portion positioned outside said body and a portion extending into one of the openings in said body, a screw extending axially into the second-named portion of the coil spring for clamping such spring to said body, and conducting means within the body maintained by the screw andcoiled spring in electrical connection with said coil spring.

5. An electrical connector comprising a body of insulating material having elongated longitudinally and transversely extending openings therein, one opening intersecting the other, a metallic coil spring having a radially enlarged portion positioned outside said body and a radially reduced portion extending into the transverse opening in said body, a screw having the head thereof accessible from the exterior of said body in a region opposite the enlarged portion of said coil spring, said screw extending into the reduced portion of the coil spring for clamping such spring to said body, and conducting means within the body in electrical connection with said reduced portion of the external coiled spring.

LESTER L. STOFFEL. ALFRED A. STARK; 

